Lamivudine prophylaxis and treatment of hepatitis B Virus-exposed recipients receiving reduced intensity conditioning hematopoietic stem cell transplants with alemtuzumab

Individuals with past exposure to hepatitis B virus (HBV) may reactivate HBV following bone marrow transplantation. Alemtuzumab (CAMPATH)-based reduced intensity conditioning bone marrow transplantation has been associated with a high incidence of viral infections. Lamivudine prophylaxis for HBV should be instituted in this setting. The management of 240 CAMPATH-based reduced intensity conditioning bone marrow transplantation, carried out over an 8-year period at Kings College Hospital, was reviewed. Hepatitis B core total antibody (anti-HBc) testing identified recipients and donors with previous HBV exposure. Fifteen donor-recipient pairs were identified as being at risk of HBV reactivation. Eight recipients of anti-HBc negative donors were HBsAg negative, anti-HBc positive pre-transplantation. Five anti-HBc negative recipients received transplants from HBsAg negative, anti-HBc positive donors. Two HBV carrier recipients had one anti-HBc negative and one positive donor, respectively. Pre-transplant lamivudine prophylaxis was given to 8/10 (80%) anti-HBc positive recipients. Although HBsAg and HBV DNA were detected 4 months after bone marrow transplantation in one patient who did not receive prophylaxis, a good antiviral response was documented on starting lamivudine. The two HBV carrier recipients had stopped lamivudine at 8 and 31 months post-bone marrow transplantation, respectively, and died of liver failure with a sharp rise in HBV DNA levels. The five anti-HBc negative recipients with anti-HBc positive donors remained HBsAg and HBV DNA negative. Although lamivudine prophylaxis prevented HBV reactivation, it is unclear at what stage post-transplantation prophylaxis can be discontinued. Close monitoring of liver function tests (LFTs), HBsAg, and HBV DNA must be undertaken even after stopping antiviral prophylaxis.     

Allogeneic hematopoietic cell transplantation following reduced intensity conditioning for treatment of myelofibrosis.

This report describes our experience with reduced intensity conditioning (RIC) allogeneic hematopoietic cell transplantation (HCT) using matched sibling and unrelated donors (MUDs) for treatment of myelofibrosis (MF). Nine patients with MF (median age, 54 years) were treated with RIC allogeneic HCT using MUDs for 7 of the 9 patients and sibling donors for 2 patients. By the Lille classification, 4 patients were characterized as having high risk, 4 as having intermediate risk, and 1 as having low risk. The RIC regimen consisted of fludarabine and a single dose of total body irradiation for the first patient and fludarabine/melphalan for the remaining 8 patients. Granulocyte colony-stimulating factor-primed peripheral blood stem cells (PBSCs) were used for all but 1 patient who received a total of 3 products because of graft failure, of which 2 were bone marrow cells and the third was PBSCs. Prophylaxis against graft-versus-host disease consisted of cyclosporin/mycophenolate with or without methotrexate. Seven patients were successfully engrafted with white blood cells, with an absolute neutrophil count > or =500 by a median of day +15 (range, 10-21 days). At the time of final fluorescence in situ hybridization and/or short tandem repeat analysis, 8 of 9 patients were chimeric, with 96%-100% donor cells and/or DNA. Five of the 9 patients were alive at the time of final contact, with a median follow-up of 32.2 months for the living patients. Overall survival probability at 1 year was 55.6% (95% confidence interval, 31.3%-77.4%). These results suggest that RIC MUD HCT using PBSCs can be an effective treatment for older patients with MF.     

Association between genetic variants in adhesion molecules and outcomes after hematopoietic cell transplants

Allogeneic hematopoietic cell transplant (HCT) is associated with a high morbidity and mortality. Adhesion molecules play an important role in endothelial activation and initiation of inflammatory response. We hypothesized that single nucleotide polymorphisms (SNPs) in the endothelial molecules may contribute to heterogeneity in HCT outcomes. We evaluated the association of 4 SNPs in ICAM1 (rs5498), PECAM1 (rs668 and rs1131012) and SELL (rs2229569) genes with acute and chronic graft‐versus‐host disease (GvHD) and those experiencing transplant‐related mortality (TRM) within 1 year among 425 allogeneic HCT recipient–donor pairs. Using a Fine and Gray proportional hazards model to evaluate the association between genetic variants and clinical outcomes, after adjustment for recipient age, race, diagnosis, disease status, gender mismatch, cytomegalovirus serostatus, gender, donor type, conditioning regimen and year of transplant, only rs5498 in the ICAM1 gene among both recipients and donors was associated with a decreased risk of TRM (P ≤ 0.02). None of the SNPs were associated with acute or chronic GvHD risk. These findings suggest that genetic variants in the vascular adhesion molecules may be used to identify patients at high risk for TRM.     

Allografting after nonmyeloablative conditioning as a treatment after a failed conventional hematopoietic cell transplant.

Outcomes with conventional allogeneic hematopoietic cell transplantation (HCT) after failed HCT are typically poor. To reduce transplantation-related mortality (TRM), 55 patients (median age, 43 years; range, 18-69 years) who had failed conventional autologous (n = 49), allogeneic (n = 4), or syngeneic (n = 2) HCT received human leukocyte antigen-matched related (n = 31) or unrelated (n = 24) donor allografts after nonmyeloablative conditioning with 2 Gy of total body irradiation or 2 Gy of total body irradiation and 90 mg/m(2) of fludarabine. Postgrafting immunosuppression consisted of cyclosporine and mycophenolate mofetil. One rejection occurred. Thirty-three patients died a median of 127 days (range, 7-834 days) after HCT: 21 of relapse, 11 of TRM, and 1 of suicide. The TRM rate on day 100 was 11% with an estimated 1-year TRM rate of 20% (95% confidence interval [CI], 9% to 31%). The median follow-up among the 22 survivors is 368 days (range, 173-796 days). Seventeen of 22 survivors are progression-free. One-year estimates of overall and progression-free survival rates are 49% (95% CI, 35% to 62%) and 28% (95% CI, 16% to 41%), respectively. Untreated disease at the time of allografting after nonmyeloablative conditioning increased the risk of death (hazard ratio = 2.4; P =.04). Although the length of follow-up is still short, it appears that encouraging outcomes can be achieved with nonmyeloablative conditioning in patients expected to have poor outcomes with conventional allografting.     

Acute and chronic graft-versus-host disease after ablative and nonmyeloablative conditioning for allogeneic hematopoietic transplantation.

In this study, we evaluated the influence of nonmyeloablative and ablative conditioning regimens on the occurrence of acute and chronic graft-versus-host disease (GVHD). One hundred thirty-seven patients undergoing matched-related sibling transplantations received the same GVHD prophylaxis. Myeloablative regimens included intravenous busulfan/cyclophosphamide (n=45) and fludarabine/melphalan (n=29). Patients in the nonmyeloablative group (n=63) received fludarabine/idarubicin/cytarabine, cisplatin/fludarabine/idarubicin, and fludarabine/cyclophosphamide. The actuarial rate of grade II to IV acute GVHD was significantly higher (hazard ratio, 3.6; 95% confidence interval, 1.5-8.8) in patients receiving ablative regimens (36%) compared with the nonmyeloablative group (12%). The cumulative incidence of chronic GVHD was higher in the ablative group (40%) compared with the nonmyeloablative group (14%). The rates were comparable within the first 200 days and were significantly higher in the ablative group beyond day 200 (hazard ratio, 5.2; 95% confidence interval, 1.2-23.2). Nonrelapse and GVHD-related mortality were relatively low in both groups. The use of the described nonmyeloablative preparative regimens was associated with a reduced incidence of grade II to IV acute GVHD and chronic GVHD compared with the busulfan/cyclophosphamide and fludarabine/melphalan transplant regimens. It is interesting to note that nonrelapse mortality with nonmyeloablative regimens in older and more debilitated patients was low (14%) and comparable to that achieved with standard high-dose regimens in younger patients.     

Secondary failure of platelet recovery after hematopoietic stem cell transplantation.

After primary recovery of platelet counts after transplantation, there can be a late persistent decline called secondary failure of platelet recovery (SFPR), which may occur although the counts of other cell lineages remain within the normal range. SFPR was defined as a decline of platelet counts below 20,000/microL for 7 consecutive days or requiring transfusion support after achieving sustained platelet counts > or = 50,000/microL without transfusions for 7 consecutive days after hematopoietic stem cell transplantation (HSCT). The study population consisted of 2871 consecutive patients receiving transplants from January 1990 to March 1997. After primary recovery of platelet counts, SFPR not due to relapse of the underlying disease was observed in 285 of 1401 (20%) patients undergoing allogeneic transplantation and 36 (8%) of 444 patients undergoing autologous transplantation, with a median time of onset after transplantation at day 63 (range, day 21-156) and day 44 (range, day 24-89), respectively. Concomitant neutropenia was seen in 57 (20%) of 285 patients undergoing allogeneic HSCT and 7 (19%) of 36 patients undergoing autologous HSCT with SFPR. By multivariable analysis, the following were factors significantly associated with SFPR after allogeneic HSCT: a transplant from an unrelated donor; a graft-versus-host disease (GVHD) prophylaxis other than methotrexate and cyclosporine; development of grade 2 through 4 acute GVHD; impaired renal or liver function; conditioning with the combination of busulfan, cyclophosphamide, and total body irradiation; stem cell dose; and infections. Cytomegalovirus infection after engraftment and source of stem cells were the only significant risk factors after autologous HSCT. The hazard rate of death was significantly higher in patients who experienced SFPR (hazard ratio = 2.6 for allogeneic HSCT; hazard ratio = 2.2 for autologous HSCT). SFPR was associated with serious complications and poor outcome after transplantation. The identification of the characteristics and risk factors for SFPR could improve patient counseling and management and lead to the design of effective treatment strategies.     

Strategies to accelerate immune recovery after allogeneic hematopoietic stem cell transplantation

The interplay existing between immune reconstitution and patient outcome has been extensively demonstrated in allogeneic hematopoietic stem cell transplantation. One of the leading causes of infection-related mortality is the slow recovery of T-cell immunity due to the conditioning regimen and/or age-related thymus damage, poor naïve T-cell output, and restricted T-cell receptor (TCR) repertoires. With the aim of improving posttransplantation immune reconstitution, several immunotherapy approaches have been explored. Donor leukocyte infusions are widely used to accelerate immune recovery, but they carry the risk of provoking graft-versus-host disease. This review will focus on sophisticated strategies of thymus function-recovery, adoptive infusion of donor-derived, allodepleted T cells, T-cell lines/clones specific for life-threatening pathogens, regulatory T cells, and of T cells transduced with suicide genes.     

T-cell receptor Vbeta repertoire after myeloablative and reduced intensity conditioning allogeneic haematopoietic stem cell transplantation

T cells play an important role in the adaptive immune system. After haematopoietic stem cell transplantation (HSCT), T-cell function is impaired. This is reflected by the emergence of opportunistic infections, infections that are often difficult to treat because of the patient's insufficient immune function. T-cell receptor reconstitution was studied using CDR3 spectratyping to analyze the diversity of the T-cell repertoire at 3, 6 and 12 months after myeloablative and reduced intensity conditioning (RIC) HSCT in 23 patients. Immune function in vitro was tested by lymphocyte stimulation at 3, 6 and 12 months after HSCT. Lower diversity in the CDR3 repertoire was demonstrated in CD4+ cells after RIC HSCT at 3 and 6 months and in CD8+ cells at 3 months compared with healthy donors. After myeloablative HSCT, lower diversity was seen at 3, 6 and 12 months in CD4+ cells and at 6 and 12 months in CD8+ cells after HSCT. Acute and chronic graft-versus-host-disease (GVHD) did not affect diversity. Responses to phytohaemagglutinin (PHA), Concanavalin A (Con A) and Staphylococcus aureus protein A were significantly lower compared with healthy donors during the first 6 months after RIC HSCT. After myeloablative HSCT, lymphocyte response to Con A was significantly lower at 3 months compared with healthy donors. Decreased responses to cytomegalovirus and varicella zoster virus antigens were seen in patients suffering from acute GVHD grade II or chronic GVHD. The T-cell repertoire is skewed under the first year after HSCT, and immune reconstitution after HSCT with myeloablative and RIC conditioning seems to be comparable. GVHD, infections and age are more important for immune reconstitution than type of conditioning.     

Impact of conditioning regimen intensity on outcome of allogeneic hematopoietic cell transplantation for advanced acute myelogenous leukemia and myelodysplastic syndrome.

We reviewed 136 patients with advanced acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS) undergoing allogeneic transplantation to assess the impact of conditioning regimen intensity on outcome. Thirty-nine patients receiving nonmyeloablative stem cell transplantation (NST) were compared with 97 patients receiving myeloablative transplantation. Patients receiving NST were at high risk for treatment-related complications given that they were older, 57 vs 43 years (P < .001), and more likely had received previous or myeloablative transplantation (54% vs 2%; P < .0001). The cumulative risk of relapse was higher for patients after NST (61% vs 38%; P = .02). The 100-day mortality was less after NST (15% vs 32%) Overall survival (OS) at 2 years was 28% for NST and 34% for myeloablative transplantation (P = .89). Progression-free survival (PFS) at 2 years was 20% for NST and 31% for myeloablative transplantation (P = .31). Cox regression analysis showed that the intensity of the conditioning regimen had no effect on either OS or PFS. Despite the high-risk features of patients with advanced AML or MDS undergoing NST, OS and PFS in these patients was similar to those in patients receiving myeloablative transplantation. These results demonstrate that dose intensity plays a significant role in control of disease after transplantation, but that this benefit is negated by increasing treatment-related mortality. These results suggest that NST is a reasonable alternative for patients with advanced AML and MDS at high risk for complications after myeloablative transplantation.     

Spinal cord transplants enhance the recovery of locomotor function after spinal cord injury at birth

Summary Fetal spinal cord transplants placed into the site of a neonatal spinal cord lesion alter the response of immature CNS neurons to injury. The transplants prevent the retrograde cell death of immature axotomized neurons and support the growth of axons into and through the site of injury. In the present experiments we used a battery of locomotor tasks to determine if these transplants are also capable of promoting the recovery of motor function after spinal cord injury at birth. Embryonic (E14) spinal cord transplants were placed into the site of a spinal cord over-hemisection in rat pups. Three groups of animals were used: 1) normal control animals, 2) animals with a spinal cord hemisection only, and 3) animals with a spinal cord transplant at the site of the hemisection. Eight to twelve weeks later, the animals were trained and videotaped while crossing runways requiring accurate foot placement and footprinted while walking on a treadmill. The videotapes and footprints were analyzed to obtain quantitative measures of locomotor function. Footprint analysis revealed that the animals' base of support during locomotion was increased by a neonatal hemisection. The base of support in animals with transplants was similar to control values. Animals with a hemisection rotated their hindlimbs further laterally than did control animals during locomotion. A transplant at the site of injury modified this response. Normal animals were able to cross a grid runway quickly with only a few errors. In contrast, animals with a hemisection took a longer time and made more errors while crossing. The presence of a transplant at the site of injury enabled the animals to cross the grid more quickly and to make fewer errors than the animals with a hemisection only. Animals that received the transplants demonstrated qualitative and quantitative improvements in several parameters of locomotion. Spinal cord transplants at the site of neonatal spinal cord injury result in enhanced sparing or recovery of motor function. We suggest that this transplant induced recovery of function is a consequence of the anatomical plasticity elicited by the transplants.     

Influence of recovery manipulation after hyperlactemia induction on the lactate minimum intensity

This study analyzed the influence of recovery phase manipulation after hyperlactemia induction on the lactate minimum intensity during treadmill running. Twelve male runners (24.6 ± 6.3 years; 172 ± 8.0 cm and 62.6 ± 6.1 kg) performed three lactate minimum tests involving passive (LMT_P) and active recoveries at 30%vVO_2max (LMT_A30) and 50%vVO_2max (LMT_A50) in the 8-min period following initial sprints. During subsequent graded exercise, lactate minimum speed and VO₂ in LMT_A50 (12.8 ± 1.5 km h⁻¹ and 40.3 ± 5.1 ml kg⁻¹ min⁻¹) were significantly lower (P < 0.05) than those in LMT_A30 (13.3 ± 1.6 km h⁻¹ and 42.9 ± 5.3 ml kg⁻¹ min⁻¹) and LMT_P (13.8 ± 1.6 km h⁻¹ and 43.6 ± 6.1 ml kg⁻¹ min⁻¹). In addition, lactate minimum speed in LMT_A30 was significantly lower (P < 0.05) than that in LMT_P. These results suggest that lactate minimum intensity is lowered by active recovery after hyperlactemia induction in an intensity-dependent manner compared to passive recovery.     

Unrelated donor status and high donor age independently affect immunologic recovery after nonmyeloablative conditioning.

The risk of cytomegalovirus (CMV) infection is higher after HLA-matched unrelated donor (URD) than after HLA-matched related donor (MRD) nonmyeloablative hematopoietic cell transplantation (HCT). We therefore investigated factors affecting immune recovery in 94 patients given HCT from MRDs (n = 51) and URDs (n = 43) after 2-Gy total body irradiation with or without fludarabine and postgrafting immunosuppression with mycophenolate mofetil and cyclosporine. CD4 T cells counts remained below normal values during the first year after HCT in both patient groups. This included abnormally low counts each of naive CD4 T cells and memory CD4 T cells. Conversely, CD8 T cell counts reached the 10th percentile of normal 6 months after HCT in MRD and URD recipients. On day 30 after HCT, URD recipients had lower counts of B cells (P = .02), naive CD4 T cells (P = .04), memory CD4 T cells (P = .005), memory CD8 T cells (P = .005), and CMV-specific T helper cells (P = .007) than had MRD recipients. This delay in CMV-specific immune reconstitution translated into increased frequency of CMV antigenemia among URD recipients during the first 100 days after HCT. Older donor age was associated with low counts of naive CD4 T cells on days 180-365 after HCT (P = .003). Further, low numbers of T cells and CD34(+) cells in the graft and development of acute graft-versus-host disease were associated with impaired immune recovery of naive CD4 T cells and B cells. In summary, immunologic recovery was poor the first year after nonmyeloablative conditioning and was delayed among URD recipients in comparison with MRD recipients. Other factors significantly associated with delayed immune recovery were advanced donor age, low numbers of CD34 and T cells in the graft, and development of graft-versus-host disease.     

Safety of posaconazole and sirolimus coadministration in allogeneic hematopoietic stem cell transplants

Sirolimus is used in allogeneic hematopoietic stem cell transplants (HSCTs) for prevention and treatment of graft-versus-host disease (GVHD). Posaconazole is used in this population for invasive fungal disease (IFD) prophylaxis and treatment. As posaconazole strongly inhibits CYP3A4, concurrent administration of sirolimus, a CYP3A4 substrate, and posaconazole has been reported to increase sirolimus drug exposure substantially. Coadministration of posaconazole and sirolimus is contraindicated by the manufacturer of posaconazole. We identified 15 patients who underwent HSCTs at our institution receiving a steady-state dose of sirolimus who subsequently started posaconazole therapy from January 2006 to March 2009. We recorded baseline characteristics, drug administration details, and potential adverse effects related to either drug. All patients underwent HSCTs for treatment of hematologic malignancy. All patients were initially prescribed sirolimus for GVHD prophylaxis and continued therapy after developing GVHD. Twelve patients (80%) received posaconazole for IFD prophylaxis in the setting of GVHD and 3 (20%) for IFD treatment. Patients received sirolimus and posaconazole concurrently for a median of 78 days (interquartile range [IQR] 25-177; range, 6-503). The median daily dose of sirolimus (2 mg/day) before initiation of posaconazole was reduced 50% to a median daily dose of 1 mg/day at steady state. Six patients experienced sirolimus trough levels greater than 12 ng/mL during coadministration, but only 1 patient experienced an adverse event potentially associated with sirolimus exposure during the first month of coadministration. This patient's sirolimus dose was empirically reduced by only 30% on posaconazole initiation. Concurrent sirolimus and posaconazole use seems to be well tolerated with a 33% to 50% empiric sirolimus dose reduction and close monitoring of serum sirolimus trough levels at the time of posaconazole initiation.     

HLA-matched unrelated donor hematopoietic cell transplantation after nonmyeloablative conditioning for patients with chronic myeloid leukemia.

We evaluated 10/10 HLA antigen-matched unrelated hematopoietic cell transplantation (HCT) after nonmyeloablative conditioning with fludarabine 3 x 30 mg/m2 and 2 Gy of total body irradiation as treatment for patients with chronic myeloid leukemia who were ineligible for conventional HCT. Data from 21 consecutive patients in first chronic phase (CP1; n = 12), accelerated phase (AP; n = 5), second CP (CP2; n = 3), and blast crisis (n = 1) were analyzed. Stem cell sources were bone marrow (n = 4) or granulocyte colony-stimulating factor-mobilized peripheral blood mononuclear cells (G-PBMCs; n = 17). The patient who underwent transplantation in blast crisis died on day 21 (too early to be evaluated for engraftment) from progressive disease. Sustained engraftment was achieved in 5 of 12 patients who underwent transplantation in CP1, 4 of 5 patients who underwent transplantation in AP, and 2 of 3 patients who underwent transplantation in CP2, whereas 9 patients rejected their grafts between 28 and 400 days after HCT. Specifically, 1 of 4 marrow recipients and 10 of 17 G-PBMC recipients achieved sustained engraftment. Graft rejections were nonfatal in all cases and were followed by autologous reconstitution with persistence or recurrence of chronic myeloid leukemia. Seven of 11 patients with sustained engraftment--including all 5 patients in CP1, 2 of 4 patients in AP, and neither of the 2 patients in CP2--were alive in complete cytogenetic remissions 118 to 1205 days (median, 867 days) after HCT. Two of the remaining 4 patients died of nonrelapse causes in complete (n = 1) or major (n = 1) cytogenetic remissions, and 2 died of progressive disease. Further efforts are directed at reducing the risk of graft rejection by exclusive use of G-PBMC and increasing the degree of pretransplantation immunosuppression.     

Multilineage hematopoietic recovery with concomitant antitumor effects using low dose Interleukin-12 in myelosuppressed tumor-bearing mice

Background  

Interleukin-12 (IL-12) is a cytokine well known for its role in immunity. A lesser known function of IL-12 is its role in hematopoiesis. The promising data obtained in the preclinical models of antitumor immunotherapy raised hope that IL-12 could be a powerful therapeutic agent against cancer. However, excessive clinical toxicity, largely due to repeat dose regimens, and modest clinical response observed in the clinical trials have pointed to the necessity to design protocols that minimize toxicity without affecting the anti-tumor effect of IL-12. We have focused on the lesser known role of IL-12 in hematopoiesis and hypothesized that an important clinical role for IL-12 in cancer may be as an adjuvant hematological cancer therapy. In this putative clinical function, IL-12 is utilized for the prevention of cancer therapy-related cytopenias, while providing concomitant anti-tumor responses over and above responses observed with the primary therapy alone. This putative clinical function of IL-12 focuses on the dual role of IL-12 in hematopoiesis and immunity.     

Alternate donor hematopoietic cell transplantation (HCT) in non-Hodgkin lymphoma using lower intensity conditioning: a report from the CIBMTR

We analyzed the outcomes of 248 (61% male) adult recipients of HLA-matched unrelated and HLA-mismatched related donor hematopoietic cell transplantation (HCT) for non-Hodgkin lymphoma (NHL) after reduced or lower intensity conditioning (RIC), reported to the Center for International Blood and Marrow Transplant Research (CIBMTR) from 1997 to 2004. Median age was 52 (range: 18-72 years); 31% had a Karnofsky performance score <90. Follicular NHL (43%) was the major histology. Incidence of grades II-IV acute graft-versus-host disease (aGVHD) was 43% at 100 days; and chronic GVHD (cGVHD) was 44% at 3 years. Treatment-related mortality (TRM) at 100 days was 24%. Three-year overall survival (OS) and progression-free survival (PFS) were 41% and 32%, respectively. In multivariate analysis, use of antithymocyte globulin (ATG) and HLA mismatch were associated with increased TRM. High-grade histology, ATG use, and chemotherapy resistance were associated with lower PFS. Older age, shorter interval from diagnosis to HCT, non-total body irridiation (TBI) conditioning regimens, ex?vivo T cell depletion, and HLA-mismatched unrelated donors were associated with mortality. GVHD did not influence relapse or PFS. Older age, aggressive histology, and chemotherapy resistance correlated with poorer survival. For selected patients with NHL, lack of an available sibling donor should not be a barrier to allogeneic HCT.